Vehicle front body structures of the type having an apron frame (upper member) disposed outward of a front side frame and extending along an upper portion of a front wheel house are known heretofore, as disclosed, for example, in Japanese Patent (JP-B2) No. 2,516,212.
As shown in FIG. 7 hereof, the disclosed vehicle front body structure 100 includes a front side frame 103 extending longitudinally of the vehicle body and disposed on a lower side edge of a wheel house 102, and an apron frame (upper member) 105 disposed outwardly of the front side frame 101. The apron frame 105 has a central portion 106 curved or bent into a curvature extending along an upper edge of the wheel house 101. The thus curved central portion 106 has a steep down-slope when viewed in a forward direction of the vehicle body.
With this arrangement, when the apron frame 105 is subjected to a backward force or load acting on a front end 108 thereof, as indicated by a profiled arrow shown in FIG. 7, the curved central portion 106 of the apron frame 105 will undergo yielding or deformation in a radial inward direction of the wheel house 101. Thus, the apron frame 105 with curved central portion 106 does not contribute to distribution of the load to a front pillar disposed rearward of the apron frame 105.
Another example of the known vehicle front body structure is disclosed in Japanese Patent Laid-open Publication (JP-A) No. 2003-40142. As shown in FIG. 8 hereof, the disclosed vehicle front body structure 110 includes a front side frame 111 extending in a longitudinal direction of the vehicle body, and an upper member 114 extending forwardly on the down grade from the lower end of a front pillar 112 and having a front end 116 connected via a connecting member 117 and a side down member 118 to a front end portion 122 of the front side frame 111. The upper member 112 includes a rear end portion 113 extending forwardly from the lower end of the front pillar 112, a downwardly inclined central portion 119 extending forwardly from a front end of the rear end portion 113, and a substantial vertical front end portion 121 extending vertically downward from a front end of the central portion 119. A lower end of the vertical end portion 121 forms the front end 116 of the upper member 114 that is connected via the connecting member 117 and the side down member 118 to the front end portion 122 of the front side frame 111.
By thus connecting the vertical front end portion 121 to the front side frame 111 via the connecting member 117 and the side down member 118, the upper member 114 is structurally reinforced. However, due to the use of the connecting member 117 and the side down member 118, a corresponding increase in weight of the entire vehicle front body structure 110 is inevitable. Additionally, due to the presence of the connecting member 117 and the side down member 118, a space 123 provided on a lateral outer side of the front end portion 122 of the front side frame 111 is relatively small and this poses a certain limit or restriction to the design and arrangement of a vehicle part such as a front fog light adapted to be installed in the space 123.